package com.iboxpay.settlement.gateway.common.util;

import java.util.Map;

import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;

/**
 * 
 * 以静态变量保存Spring ApplicationContext, 可在任何代码任何地方任何时候中取出ApplicaitonContext.
 **/

public class SpringContextHolder implements ApplicationContextAware {

	private static ApplicationContext applicationContext;

	/**
	 * 
	 * 实现ApplicationContextAware接口的context注入函数, 将其存入静态变量.
	 */

	public void setApplicationContext(ApplicationContext applicationContext) {
		SpringContextHolder.applicationContext = applicationContext;
	}
	/**
	 * 
	 * 取得存储在静态变量中的ApplicationContext.
	 */
	public static ApplicationContext getApplicationContext() {
		checkApplicationContext();
		return applicationContext;

	}

	/**
	 * 
	 * 从静态变量ApplicationContext中取得Bean, 自动转型为所赋值对象的类型.
	 */

	@SuppressWarnings("unchecked")
	public static <T> T getBean(String name) {

		checkApplicationContext();

		return (T) applicationContext.getBean(name);

	}

	/**
	 * 
	 * 从静态变量ApplicationContext中取得Bean, 自动转型为所赋值对象的类型.
	 * 
	 * 如果有多个Bean符合Class, 取出第一个.
	 */

	@SuppressWarnings({ "unchecked", "rawtypes" })
	public static <T> T getBean(Class<T> clazz) {

		checkApplicationContext();

		Map beanMaps = applicationContext.getBeansOfType(clazz);

		if (beanMaps != null && !beanMaps.isEmpty()) {

			return (T) beanMaps.values().iterator().next();

		} else {

			return null;

		}

	}

	private static void checkApplicationContext() {

		if (applicationContext == null) {

			throw new IllegalStateException(
					"applicaitonContext未注入,请在applicationContext.xml中定义SpringContextHolder");

		}

	}

}